gold/archive.cc

   1 // archive.cc -- archive support for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <cerrno>
  26 #include <cstring>
  27 #include <climits>
  28 #include <vector>
  29 #include "libiberty.h"
  30 #include "filenames.h"
  31
  32 #include "elfcpp.h"
  33 #include "options.h"
  34 #include "mapfile.h"
  35 #include "fileread.h"
  36 #include "readsyms.h"
  37 #include "symtab.h"
  38 #include "object.h"
  39 #include "layout.h"
  40 #include "archive.h"
  41 #include "plugin.h"
  42 #include "incremental.h"
  43
  44 namespace gold
  45 {
  46
  47 // Library_base methods.
  48
  49 // Determine whether a definition of SYM_NAME should cause an archive
  50 // library member to be included in the link.  Returns SHOULD_INCLUDE_YES
  51 // if the symbol is referenced but not defined, SHOULD_INCLUDE_NO if the
  52 // symbol is already defined, and SHOULD_INCLUDE_UNKNOWN if the symbol is
  53 // neither referenced nor defined.
  54
  55 Library_base::Should_include
  56 Library_base::should_include_member(Symbol_table* symtab, Layout* layout,
  57                                     const char* sym_name, Symbol** symp,
  58                                     std::string* why, char** tmpbufp,
  59                                     size_t* tmpbuflen)
  60 {
  61   // In an object file, and therefore in an archive map, an
  62   // '@' in the name separates the symbol name from the
  63   // version name.  If there are two '@' characters, this is
  64   // the default version.
  65   char* tmpbuf = *tmpbufp;
  66   const char* ver = strchr(sym_name, '@');
  67   bool def = false;
  68   if (ver != NULL)
  69     {
  70       size_t symlen = ver - sym_name;
  71       if (symlen + 1 > *tmpbuflen)
  72         {
  73           tmpbuf = static_cast<char*>(xrealloc(tmpbuf, symlen + 1));
  74           *tmpbufp = tmpbuf;
  75           *tmpbuflen = symlen + 1;
  76         }
  77       memcpy(tmpbuf, sym_name, symlen);
  78       tmpbuf[symlen] = '\0';
  79       sym_name = tmpbuf;
  80
  81       ++ver;
  82       if (*ver == '@')
  83         {
  84           ++ver;
  85           def = true;
  86         }
  87     }
  88
  89   Symbol* sym = symtab->lookup(sym_name, ver);
  90   if (def
  91       && ver != NULL
  92       && (sym == NULL
  93           || !sym->is_undefined()
  94           || sym->binding() == elfcpp::STB_WEAK))
  95     sym = symtab->lookup(sym_name, NULL);
  96
  97   *symp = sym;
  98
  99   if (sym == NULL)
 100     {
 101       // Check whether the symbol was named in a -u option.
 102       if (parameters->options().is_undefined(sym_name))
 103         {
 104           *why = "-u ";
 105           *why += sym_name;
 106         }
 107       else if (layout->script_options()->is_referenced(sym_name))
 108         {
 109           size_t alc = 100 + strlen(sym_name);
 110           char* buf = new char[alc];
 111           snprintf(buf, alc, _("script or expression reference to %s"),
 112                    sym_name);
 113           *why = buf;
 114           delete[] buf;
 115         }
 116       else if (strcmp(sym_name, parameters->entry()) == 0)
 117         {
 118           *why = "entry symbol ";
 119           *why += sym_name;
 120         }
 121       else
 122         return Library_base::SHOULD_INCLUDE_UNKNOWN;
 123     }
 124   else if (!sym->is_undefined())
 125     return Library_base::SHOULD_INCLUDE_NO;
 126   // PR 12001: Do not include an archive when the undefined
 127   // symbol has actually been defined on the command line.
 128   else if (layout->script_options()->is_pending_assignment(sym_name))
 129     return Library_base::SHOULD_INCLUDE_NO;
 130   else if (sym->binding() == elfcpp::STB_WEAK)
 131     return Library_base::SHOULD_INCLUDE_UNKNOWN;
 132
 133   return Library_base::SHOULD_INCLUDE_YES;
 134 }
 135
 136 // The header of an entry in the archive.  This is all readable text,
 137 // padded with spaces where necessary.  If the contents of an archive
 138 // are all text file, the entire archive is readable.
 139
 140 struct Archive::Archive_header
 141 {
 142   // The entry name.
 143   char ar_name[16];
 144   // The file modification time.
 145   char ar_date[12];
 146   // The user's UID in decimal.
 147   char ar_uid[6];
 148   // The user's GID in decimal.
 149   char ar_gid[6];
 150   // The file mode in octal.
 151   char ar_mode[8];
 152   // The file size in decimal.
 153   char ar_size[10];
 154   // The final magic code.
 155   char ar_fmag[2];
 156 };
 157
 158 // Class Archive static variables.
 159 unsigned int Archive::total_archives;
 160 unsigned int Archive::total_members;
 161 unsigned int Archive::total_members_loaded;
 162
 163 // Archive methods.
 164
 165 const char Archive::armag[sarmag] =
 166 {
 167   '!', '<', 'a', 'r', 'c', 'h', '>', '\n'
 168 };
 169
 170 const char Archive::armagt[sarmag] =
 171 {
 172   '!', '<', 't', 'h', 'i', 'n', '>', '\n'
 173 };
 174
 175 const char Archive::arfmag[2] = { '`', '\n' };
 176
 177 Archive::Archive(const std::string& name, Input_file* input_file,
 178                  bool is_thin_archive, Dirsearch* dirpath, Task* task)
 179   : Library_base(task), name_(name), input_file_(input_file), armap_(),
 180     armap_names_(), extended_names_(), armap_checked_(), seen_offsets_(),
 181     members_(), is_thin_archive_(is_thin_archive), included_member_(false),
 182     nested_archives_(), dirpath_(dirpath), num_members_(0)
 183 {
 184   this->no_export_ =
 185     parameters->options().check_excluded_libs(input_file->found_name());
 186 }
 187
 188 // Set up the archive: read the symbol map and the extended name
 189 // table.
 190
 191 void
 192 Archive::setup()
 193 {
 194   // We need to ignore empty archives.
 195   if (this->input_file_->file().filesize() == sarmag)
 196     return;
 197
 198   // The first member of the archive should be the symbol table.
 199   std::string armap_name;
 200   off_t header_size = this->read_header(sarmag, false, &armap_name, NULL);
 201   if (header_size == -1)
 202     return;
 203
 204   section_size_type armap_size = convert_to_section_size_type(header_size);
 205   off_t off = sarmag;
 206   if (armap_name.empty())
 207     {
 208       this->read_armap(sarmag + sizeof(Archive_header), armap_size);
 209       off = sarmag + sizeof(Archive_header) + armap_size;
 210     }
 211   else if (!this->input_file_->options().whole_archive())
 212     gold_error(_("%s: no archive symbol table (run ranlib)"),
 213                this->name().c_str());
 214
 215   // See if there is an extended name table.  We cache these views
 216   // because it is likely that we will want to read the following
 217   // header in the add_symbols routine.
 218   if ((off & 1) != 0)
 219     ++off;
 220   std::string xname;
 221   header_size = this->read_header(off, true, &xname, NULL);
 222   if (header_size == -1)
 223     return;
 224
 225   section_size_type extended_size = convert_to_section_size_type(header_size);
 226   if (xname == "/")
 227     {
 228       const unsigned char* p = this->get_view(off + sizeof(Archive_header),
 229                                               extended_size, false, true);
 230       const char* px = reinterpret_cast<const char*>(p);
 231       this->extended_names_.assign(px, extended_size);
 232     }
 233   bool preread_syms = (parameters->options().threads()
 234                        && parameters->options().preread_archive_symbols());
 235 #ifndef ENABLE_THREADS
 236   preread_syms = false;
 237 #else
 238   if (parameters->options().has_plugins())
 239     preread_syms = false;
 240 #endif
 241   if (preread_syms)
 242     this->read_all_symbols();
 243 }
 244
 245 // Unlock any nested archives.
 246
 247 void
 248 Archive::unlock_nested_archives()
 249 {
 250   for (Nested_archive_table::iterator p = this->nested_archives_.begin();
 251        p != this->nested_archives_.end();
 252        ++p)
 253     {
 254       p->second->unlock(this->task_);
 255     }
 256 }
 257
 258 // Read the archive symbol map.
 259
 260 void
 261 Archive::read_armap(off_t start, section_size_type size)
 262 {
 263   // To count the total number of archive members, we'll just count
 264   // the number of times the file offset changes.  Since most archives
 265   // group the symbols in the armap by object, this ought to give us
 266   // an accurate count.
 267   off_t last_seen_offset = -1;
 268
 269   // Read in the entire armap.
 270   const unsigned char* p = this->get_view(start, size, true, false);
 271
 272   // Numbers in the armap are always big-endian.
 273   const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
 274   unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
 275   ++pword;
 276
 277   // Note that the addition is in units of sizeof(elfcpp::Elf_Word).
 278   const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
 279   section_size_type names_size =
 280     reinterpret_cast<const char*>(p) + size - pnames;
 281   this->armap_names_.assign(pnames, names_size);
 282
 283   this->armap_.resize(nsyms);
 284
 285   section_offset_type name_offset = 0;
 286   for (unsigned int i = 0; i < nsyms; ++i)
 287     {
 288       this->armap_[i].name_offset = name_offset;
 289       this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
 290       name_offset += strlen(pnames + name_offset) + 1;
 291       ++pword;
 292       if (this->armap_[i].file_offset != last_seen_offset)
 293         {
 294           last_seen_offset = this->armap_[i].file_offset;
 295           ++this->num_members_;
 296         }
 297     }
 298
 299   if (static_cast<section_size_type>(name_offset) > names_size)
 300     gold_error(_("%s: bad archive symbol table names"),
 301                this->name().c_str());
 302
 303   // This array keeps track of which symbols are for archive elements
 304   // which we have already included in the link.
 305   this->armap_checked_.resize(nsyms);
 306 }
 307
 308 // Read the header of an archive member at OFF.  Fail if something
 309 // goes wrong.  Return the size of the member.  Set *PNAME to the name
 310 // of the member.
 311
 312 off_t
 313 Archive::read_header(off_t off, bool cache, std::string* pname,
 314                      off_t* nested_off)
 315 {
 316   const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
 317                                           cache);
 318   const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
 319   return this->interpret_header(hdr, off,  pname, nested_off);
 320 }
 321
 322 // Interpret the header of HDR, the header of the archive member at
 323 // file offset OFF.  Return the size of the member, or -1 if something
 324 // has gone wrong.  Set *PNAME to the name of the member.
 325
 326 off_t
 327 Archive::interpret_header(const Archive_header* hdr, off_t off,
 328                           std::string* pname, off_t* nested_off) const
 329 {
 330   if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
 331     {
 332       gold_error(_("%s: malformed archive header at %zu"),
 333                  this->name().c_str(), static_cast<size_t>(off));
 334       return -1;
 335     }
 336
 337   const int size_string_size = sizeof hdr->ar_size;
 338   char size_string[size_string_size + 1];
 339   memcpy(size_string, hdr->ar_size, size_string_size);
 340   char* ps = size_string + size_string_size;
 341   while (ps[-1] == ' ')
 342     --ps;
 343   *ps = '\0';
 344
 345   errno = 0;
 346   char* end;
 347   off_t member_size = strtol(size_string, &end, 10);
 348   if (*end != '\0'
 349       || member_size < 0
 350       || (member_size == LONG_MAX && errno == ERANGE))
 351     {
 352       gold_error(_("%s: malformed archive header size at %zu"),
 353                  this->name().c_str(), static_cast<size_t>(off));
 354       return -1;
 355     }
 356
 357   if (hdr->ar_name[0] != '/')
 358     {
 359       const char* name_end = strchr(hdr->ar_name, '/');
 360       if (name_end == NULL
 361           || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
 362         {
 363           gold_error(_("%s: malformed archive header name at %zu"),
 364                      this->name().c_str(), static_cast<size_t>(off));
 365           return -1;
 366         }
 367       pname->assign(hdr->ar_name, name_end - hdr->ar_name);
 368       if (nested_off != NULL)
 369         *nested_off = 0;
 370     }
 371   else if (hdr->ar_name[1] == ' ')
 372     {
 373       // This is the symbol table.
 374       if (!pname->empty())
 375         pname->clear();
 376     }
 377   else if (hdr->ar_name[1] == '/')
 378     {
 379       // This is the extended name table.
 380       pname->assign(1, '/');
 381     }
 382   else
 383     {
 384       errno = 0;
 385       long x = strtol(hdr->ar_name + 1, &end, 10);
 386       long y = 0;
 387       if (*end == ':')
 388         y = strtol(end + 1, &end, 10);
 389       if (*end != ' '
 390           || x < 0
 391           || (x == LONG_MAX && errno == ERANGE)
 392           || static_cast<size_t>(x) >= this->extended_names_.size())
 393         {
 394           gold_error(_("%s: bad extended name index at %zu"),
 395                      this->name().c_str(), static_cast<size_t>(off));
 396           return -1;
 397         }
 398
 399       const char* name = this->extended_names_.data() + x;
 400       const char* name_end = strchr(name, '\n');
 401       if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
 402           || name_end[-1] != '/')
 403         {
 404           gold_error(_("%s: bad extended name entry at header %zu"),
 405                      this->name().c_str(), static_cast<size_t>(off));
 406           return -1;
 407         }
 408       pname->assign(name, name_end - 1 - name);
 409       if (nested_off != NULL)
 410         *nested_off = y;
 411     }
 412
 413   return member_size;
 414 }
 415
 416 // An archive member iterator.
 417
 418 class Archive::const_iterator
 419 {
 420  public:
 421   // The header of an archive member.  This is what this iterator
 422   // points to.
 423   struct Header
 424   {
 425     // The name of the member.
 426     std::string name;
 427     // The file offset of the member.
 428     off_t off;
 429     // The file offset of a nested archive member.
 430     off_t nested_off;
 431     // The size of the member.
 432     off_t size;
 433   };
 434
 435   const_iterator(Archive* archive, off_t off)
 436     : archive_(archive), off_(off)
 437   { this->read_next_header(); }
 438
 439   const Header&
 440   operator*() const
 441   { return this->header_; }
 442
 443   const Header*
 444   operator->() const
 445   { return &this->header_; }
 446
 447   const_iterator&
 448   operator++()
 449   {
 450     if (this->off_ == this->archive_->file().filesize())
 451       return *this;
 452     this->off_ += sizeof(Archive_header);
 453     if (!this->archive_->is_thin_archive())
 454       this->off_ += this->header_.size;
 455     if ((this->off_ & 1) != 0)
 456       ++this->off_;
 457     this->read_next_header();
 458     return *this;
 459   }
 460
 461   const_iterator
 462   operator++(int)
 463   {
 464     const_iterator ret = *this;
 465     ++*this;
 466     return ret;
 467   }
 468
 469   bool
 470   operator==(const const_iterator p) const
 471   { return this->off_ == p->off; }
 472
 473   bool
 474   operator!=(const const_iterator p) const
 475   { return this->off_ != p->off; }
 476
 477  private:
 478   void
 479   read_next_header();
 480
 481   // The underlying archive.
 482   Archive* archive_;
 483   // The current offset in the file.
 484   off_t off_;
 485   // The current archive header.
 486   Header header_;
 487 };
 488
 489 // Read the next archive header.
 490
 491 void
 492 Archive::const_iterator::read_next_header()
 493 {
 494   off_t filesize = this->archive_->file().filesize();
 495   while (true)
 496     {
 497       if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
 498         {
 499           if (filesize != this->off_)
 500             {
 501               gold_error(_("%s: short archive header at %zu"),
 502                          this->archive_->filename().c_str(),
 503                          static_cast<size_t>(this->off_));
 504               this->off_ = filesize;
 505             }
 506           this->header_.off = filesize;
 507           return;
 508         }
 509
 510       unsigned char buf[sizeof(Archive_header)];
 511       this->archive_->file().read(this->off_, sizeof(Archive_header), buf);
 512
 513       const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
 514       off_t size = this->archive_->interpret_header(hdr, this->off_,
 515                                                     &this->header_.name,
 516                                                     &this->header_.nested_off);
 517       if (size == -1)
 518         {
 519           this->header_.off = filesize;
 520           return;
 521         }
 522
 523       this->header_.size = size;
 524       this->header_.off = this->off_;
 525
 526       // Skip special members.
 527       if (!this->header_.name.empty() && this->header_.name != "/")
 528         return;
 529
 530       this->off_ += sizeof(Archive_header) + this->header_.size;
 531       if ((this->off_ & 1) != 0)
 532         ++this->off_;
 533     }
 534 }
 535
 536 // Initial iterator.
 537
 538 Archive::const_iterator
 539 Archive::begin()
 540 {
 541   return Archive::const_iterator(this, sarmag);
 542 }
 543
 544 // Final iterator.
 545
 546 Archive::const_iterator
 547 Archive::end()
 548 {
 549   return Archive::const_iterator(this, this->input_file_->file().filesize());
 550 }
 551
 552 // Get the file and offset for an archive member, which may be an
 553 // external member of a thin archive.  Set *INPUT_FILE to the
 554 // file containing the actual member, *MEMOFF to the offset
 555 // within that file (0 if not a nested archive), and *MEMBER_NAME
 556 // to the name of the archive member.  Return TRUE on success.
 557
 558 bool
 559 Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
 560                              off_t* memsize, std::string* member_name)
 561 {
 562   off_t nested_off;
 563
 564   *memsize = this->read_header(off, false, member_name, &nested_off);
 565   if (*memsize == -1)
 566     return false;
 567
 568   *input_file = this->input_file_;
 569   *memoff = off + static_cast<off_t>(sizeof(Archive_header));
 570
 571   if (!this->is_thin_archive_)
 572     return true;
 573
 574   // Adjust a relative pathname so that it is relative
 575   // to the directory containing the archive.
 576   if (!IS_ABSOLUTE_PATH(member_name->c_str()))
 577     {
 578       const char* arch_path = this->filename().c_str();
 579       const char* basename = lbasename(arch_path);
 580       if (basename > arch_path)
 581         member_name->replace(0, 0,
 582                              this->filename().substr(0, basename - arch_path));
 583     }
 584
 585   if (nested_off > 0)
 586     {
 587       // This is a member of a nested archive.  Open the containing
 588       // archive if we don't already have it open, then do a recursive
 589       // call to include the member from that archive.
 590       Archive* arch;
 591       Nested_archive_table::const_iterator p =
 592         this->nested_archives_.find(*member_name);
 593       if (p != this->nested_archives_.end())
 594         arch = p->second;
 595       else
 596         {
 597           Input_file_argument* input_file_arg =
 598             new Input_file_argument(member_name->c_str(),
 599                                     Input_file_argument::INPUT_FILE_TYPE_FILE,
 600                                     "", false, parameters->options());
 601           *input_file = new Input_file(input_file_arg);
 602           int dummy = 0;
 603           if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 604             return false;
 605           arch = new Archive(*member_name, *input_file, false, this->dirpath_,
 606                              this->task_);
 607           arch->setup();
 608           std::pair<Nested_archive_table::iterator, bool> ins =
 609             this->nested_archives_.insert(std::make_pair(*member_name, arch));
 610           gold_assert(ins.second);
 611         }
 612       return arch->get_file_and_offset(nested_off, input_file, memoff,
 613                                        memsize, member_name);
 614     }
 615
 616   // This is an external member of a thin archive.  Open the
 617   // file as a regular relocatable object file.
 618   Input_file_argument* input_file_arg =
 619       new Input_file_argument(member_name->c_str(),
 620                               Input_file_argument::INPUT_FILE_TYPE_FILE,
 621                               "", false, this->input_file_->options());
 622   *input_file = new Input_file(input_file_arg);
 623   int dummy = 0;
 624   if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
 625     return false;
 626
 627   *memoff = 0;
 628   *memsize = (*input_file)->file().filesize();
 629   return true;
 630 }
 631
 632 // Return an ELF object for the member at offset OFF.  If
 633 // PUNCONFIGURED is not NULL, then if the ELF object has an
 634 // unsupported target type, set *PUNCONFIGURED to true and return
 635 // NULL.
 636
 637 Object*
 638 Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
 639 {
 640   if (punconfigured != NULL)
 641     *punconfigured = false;
 642
 643   Input_file* input_file;
 644   off_t memoff;
 645   off_t memsize;
 646   std::string member_name;
 647   if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
 648                                  &member_name))
 649     return NULL;
 650
 651   if (parameters->options().has_plugins())
 652     {
 653       Object* obj = parameters->options().plugins()->claim_file(input_file,
 654                                                                 memoff,
 655                                                                 memsize);
 656       if (obj != NULL)
 657         {
 658           // The input file was claimed by a plugin, and its symbols
 659           // have been provided by the plugin.
 660           return obj;
 661         }
 662     }
 663
 664   const unsigned char* ehdr;
 665   int read_size;
 666   if (!is_elf_object(input_file, memoff, &ehdr, &read_size))
 667     {
 668       gold_error(_("%s: member at %zu is not an ELF object"),
 669                  this->name().c_str(), static_cast<size_t>(off));
 670       return NULL;
 671     }
 672
 673   Object* obj = make_elf_object((std::string(this->input_file_->filename())
 674                                  + "(" + member_name + ")"),
 675                                 input_file, memoff, ehdr, read_size,
 676                                 punconfigured);
 677   if (obj == NULL)
 678     return NULL;
 679   obj->set_no_export(this->no_export());
 680   return obj;
 681 }
 682
 683 // Read the symbols from all the archive members in the link.
 684
 685 void
 686 Archive::read_all_symbols()
 687 {
 688   for (Archive::const_iterator p = this->begin();
 689        p != this->end();
 690        ++p)
 691     this->read_symbols(p->off);
 692 }
 693
 694 // Read the symbols from an archive member in the link.  OFF is the file
 695 // offset of the member header.
 696
 697 void
 698 Archive::read_symbols(off_t off)
 699 {
 700   Object* obj = this->get_elf_object_for_member(off, NULL);
 701   if (obj == NULL)
 702     return;
 703
 704   Read_symbols_data* sd = new Read_symbols_data;
 705   obj->read_symbols(sd);
 706   Archive_member member(obj, sd);
 707   this->members_[off] = member;
 708 }
 709
 710 // Select members from the archive and add them to the link.  We walk
 711 // through the elements in the archive map, and look each one up in
 712 // the symbol table.  If it exists as a strong undefined symbol, we
 713 // pull in the corresponding element.  We have to do this in a loop,
 714 // since pulling in one element may create new undefined symbols which
 715 // may be satisfied by other objects in the archive.  Return true in
 716 // the normal case, false if the first member we tried to add from
 717 // this archive had an incompatible target.
 718
 719 bool
 720 Archive::add_symbols(Symbol_table* symtab, Layout* layout,
 721                      Input_objects* input_objects, Mapfile* mapfile)
 722 {
 723   ++Archive::total_archives;
 724
 725   if (this->input_file_->options().whole_archive())
 726     return this->include_all_members(symtab, layout, input_objects,
 727                                      mapfile);
 728
 729   Archive::total_members += this->num_members_;
 730
 731   input_objects->archive_start(this);
 732
 733   const size_t armap_size = this->armap_.size();
 734
 735   // This is a quick optimization, since we usually see many symbols
 736   // in a row with the same offset.  last_seen_offset holds the last
 737   // offset we saw that was present in the seen_offsets_ set.
 738   off_t last_seen_offset = -1;
 739
 740   // Track which symbols in the symbol table we've already found to be
 741   // defined.
 742
 743   char* tmpbuf = NULL;
 744   size_t tmpbuflen = 0;
 745   bool added_new_object;
 746   do
 747     {
 748       added_new_object = false;
 749       for (size_t i = 0; i < armap_size; ++i)
 750         {
 751           if (this->armap_checked_[i])
 752             continue;
 753           if (this->armap_[i].file_offset == last_seen_offset)
 754             {
 755               this->armap_checked_[i] = true;
 756               continue;
 757             }
 758           if (this->seen_offsets_.find(this->armap_[i].file_offset)
 759               != this->seen_offsets_.end())
 760             {
 761               this->armap_checked_[i] = true;
 762               last_seen_offset = this->armap_[i].file_offset;
 763               continue;
 764             }
 765
 766           const char* sym_name = (this->armap_names_.data()
 767                                   + this->armap_[i].name_offset);
 768
 769           Symbol* sym;
 770           std::string why;
 771           Archive::Should_include t =
 772             Archive::should_include_member(symtab, layout, sym_name, &sym,
 773                                            &why, &tmpbuf, &tmpbuflen);
 774
 775           if (t == Archive::SHOULD_INCLUDE_NO
 776               || t == Archive::SHOULD_INCLUDE_YES)
 777             this->armap_checked_[i] = true;
 778
 779           if (t != Archive::SHOULD_INCLUDE_YES)
 780             continue;
 781
 782           // We want to include this object in the link.
 783           last_seen_offset = this->armap_[i].file_offset;
 784           this->seen_offsets_.insert(last_seen_offset);
 785
 786           if (!this->include_member(symtab, layout, input_objects,
 787                                     last_seen_offset, mapfile, sym,
 788                                     why.c_str()))
 789             {
 790               if (tmpbuf != NULL)
 791                 free(tmpbuf);
 792               return false;
 793             }
 794
 795           added_new_object = true;
 796         }
 797     }
 798   while (added_new_object);
 799
 800   if (tmpbuf != NULL)
 801     free(tmpbuf);
 802
 803   input_objects->archive_stop(this);
 804
 805   return true;
 806 }
 807
 808 // Return whether the archive includes a member which defines the
 809 // symbol SYM.
 810
 811 bool
 812 Archive::defines_symbol(Symbol* sym) const
 813 {
 814   const char* symname = sym->name();
 815   size_t symname_len = strlen(symname);
 816   size_t armap_size = this->armap_.size();
 817   for (size_t i = 0; i < armap_size; ++i)
 818     {
 819       if (this->armap_checked_[i])
 820         continue;
 821       const char* archive_symname = (this->armap_names_.data()
 822                                      + this->armap_[i].name_offset);
 823       if (strncmp(archive_symname, symname, symname_len) != 0)
 824         continue;
 825       char c = archive_symname[symname_len];
 826       if (c == '\0' && sym->version() == NULL)
 827         return true;
 828       if (c == '@')
 829         {
 830           const char* ver = archive_symname + symname_len + 1;
 831           if (*ver == '@')
 832             {
 833               if (sym->version() == NULL)
 834                 return true;
 835               ++ver;
 836             }
 837           if (sym->version() != NULL && strcmp(sym->version(), ver) == 0)
 838             return true;
 839         }
 840     }
 841   return false;
 842 }
 843
 844 // Include all the archive members in the link.  This is for --whole-archive.
 845
 846 bool
 847 Archive::include_all_members(Symbol_table* symtab, Layout* layout,
 848                              Input_objects* input_objects, Mapfile* mapfile)
 849 {
 850   input_objects->archive_start(this);
 851
 852   if (this->members_.size() > 0)
 853     {
 854       std::map<off_t, Archive_member>::const_iterator p;
 855       for (p = this->members_.begin();
 856            p != this->members_.end();
 857            ++p)
 858         {
 859           if (!this->include_member(symtab, layout, input_objects, p->first,
 860                                     mapfile, NULL, "--whole-archive"))
 861             return false;
 862           ++Archive::total_members;
 863         }
 864     }
 865   else
 866     {
 867       for (Archive::const_iterator p = this->begin();
 868            p != this->end();
 869            ++p)
 870         {
 871           if (!this->include_member(symtab, layout, input_objects, p->off,
 872                                     mapfile, NULL, "--whole-archive"))
 873             return false;
 874           ++Archive::total_members;
 875         }
 876     }
 877
 878   input_objects->archive_stop(this);
 879
 880   return true;
 881 }
 882
 883 // Return the number of members in the archive.  This is only used for
 884 // reports.
 885
 886 size_t
 887 Archive::count_members()
 888 {
 889   size_t ret = 0;
 890   for (Archive::const_iterator p = this->begin();
 891        p != this->end();
 892        ++p)
 893     ++ret;
 894   return ret;
 895 }
 896
 897 // Include an archive member in the link.  OFF is the file offset of
 898 // the member header.  WHY is the reason we are including this member.
 899 // Return true if we added the member or if we had an error, return
 900 // false if this was the first member we tried to add from this
 901 // archive and it had an incompatible format.
 902
 903 bool
 904 Archive::include_member(Symbol_table* symtab, Layout* layout,
 905                         Input_objects* input_objects, off_t off,
 906                         Mapfile* mapfile, Symbol* sym, const char* why)
 907 {
 908   ++Archive::total_members_loaded;
 909
 910   std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
 911   if (p != this->members_.end())
 912     {
 913       Object* obj = p->second.obj_;
 914
 915       Read_symbols_data* sd = p->second.sd_;
 916       if (mapfile != NULL)
 917         mapfile->report_include_archive_member(obj->name(), sym, why);
 918       if (input_objects->add_object(obj))
 919         {
 920           obj->layout(symtab, layout, sd);
 921           obj->add_symbols(symtab, sd, layout);
 922           this->included_member_ = true;
 923         }
 924       delete sd;
 925       return true;
 926     }
 927
 928   // If this is the first object we are including from this archive,
 929   // and we searched for this archive, most likely because it was
 930   // found via a -l option, then if the target is incompatible we want
 931   // to move on to the next archive found in the search path.
 932   bool unconfigured = false;
 933   bool* punconfigured = NULL;
 934   if (!this->included_member_ && this->searched_for())
 935     punconfigured = &unconfigured;
 936
 937   Object* obj = this->get_elf_object_for_member(off, punconfigured);
 938   if (obj == NULL)
 939     {
 940       // Return false to search for another archive, true if we found
 941       // an error.
 942       return unconfigured ? false : true;
 943     }
 944
 945   if (mapfile != NULL)
 946     mapfile->report_include_archive_member(obj->name(), sym, why);
 947
 948   Pluginobj* pluginobj = obj->pluginobj();
 949   if (pluginobj != NULL)
 950     {
 951       pluginobj->add_symbols(symtab, NULL, layout);
 952       this->included_member_ = true;
 953       return true;
 954     }
 955
 956   if (!input_objects->add_object(obj))
 957     {
 958       // If this is an external member of a thin archive, unlock the
 959       // file.
 960       if (obj->offset() == 0)
 961         obj->unlock(this->task_);
 962       delete obj;
 963     }
 964   else
 965     {
 966       {
 967         if (layout->incremental_inputs() != NULL)
 968           layout->incremental_inputs()->report_object(obj, 0, this, NULL);
 969         Read_symbols_data sd;
 970         obj->read_symbols(&sd);
 971         obj->layout(symtab, layout, &sd);
 972         obj->add_symbols(symtab, &sd, layout);
 973       }
 974
 975       // If this is an external member of a thin archive, unlock the file
 976       // for the next task.
 977       if (obj->offset() == 0)
 978         obj->unlock(this->task_);
 979
 980       this->included_member_ = true;
 981     }
 982
 983   return true;
 984 }
 985
 986 // Iterate over all unused symbols, and call the visitor class V for each.
 987
 988 void
 989 Archive::do_for_all_unused_symbols(Symbol_visitor_base* v) const
 990 {
 991   for (std::vector<Armap_entry>::const_iterator p = this->armap_.begin();
 992        p != this->armap_.end();
 993        ++p)
 994     {
 995       if (this->seen_offsets_.find(p->file_offset)
 996           == this->seen_offsets_.end())
 997         v->visit(this->armap_names_.data() + p->name_offset);
 998     }
 999 }
1000
1001 // Print statistical information to stderr.  This is used for --stats.
1002
1003 void
1004 Archive::print_stats()
1005 {
1006   fprintf(stderr, _("%s: archive libraries: %u\n"),
1007           program_name, Archive::total_archives);
1008   fprintf(stderr, _("%s: total archive members: %u\n"),
1009           program_name, Archive::total_members);
1010   fprintf(stderr, _("%s: loaded archive members: %u\n"),
1011           program_name, Archive::total_members_loaded);
1012 }
1013
1014 // Add_archive_symbols methods.
1015
1016 Add_archive_symbols::~Add_archive_symbols()
1017 {
1018   if (this->this_blocker_ != NULL)
1019     delete this->this_blocker_;
1020   // next_blocker_ is deleted by the task associated with the next
1021   // input file.
1022 }
1023
1024 // Return whether we can add the archive symbols.  We are blocked by
1025 // this_blocker_.  We block next_blocker_.  We also lock the file.
1026
1027 Task_token*
1028 Add_archive_symbols::is_runnable()
1029 {
1030   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1031     return this->this_blocker_;
1032   return NULL;
1033 }
1034
1035 void
1036 Add_archive_symbols::locks(Task_locker* tl)
1037 {
1038   tl->add(this, this->next_blocker_);
1039   tl->add(this, this->archive_->token());
1040 }
1041
1042 void
1043 Add_archive_symbols::run(Workqueue* workqueue)
1044 {
1045   // For an incremental link, begin recording layout information.
1046   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1047   if (incremental_inputs != NULL)
1048     {
1049       unsigned int arg_serial = this->input_argument_->file().arg_serial();
1050       Script_info* script_info = this->input_argument_->script_info();
1051       incremental_inputs->report_archive_begin(this->archive_, arg_serial,
1052                                                script_info);
1053     }
1054
1055   bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
1056                                            this->input_objects_,
1057                                            this->mapfile_);
1058   this->archive_->unlock_nested_archives();
1059
1060   this->archive_->release();
1061   this->archive_->clear_uncached_views();
1062
1063   if (!added)
1064     {
1065       // This archive holds object files which are incompatible with
1066       // our output file.
1067       Read_symbols::incompatible_warning(this->input_argument_,
1068                                          this->archive_->input_file());
1069       Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
1070                             this->layout_, this->dirpath_, this->dirindex_,
1071                             this->mapfile_, this->input_argument_,
1072                             this->input_group_, this->next_blocker_);
1073       delete this->archive_;
1074       return;
1075     }
1076
1077   if (this->input_group_ != NULL)
1078     this->input_group_->add_archive(this->archive_);
1079   else
1080     {
1081       // For an incremental link, finish recording the layout information.
1082       if (incremental_inputs != NULL)
1083         incremental_inputs->report_archive_end(this->archive_);
1084
1085       if (!parameters->options().has_plugins()
1086           || this->archive_->input_file()->options().whole_archive())
1087         {
1088           // We no longer need to know about this archive.
1089           delete this->archive_;
1090         }
1091       else
1092         {
1093           // The plugin interface may want to rescan this archive.
1094           parameters->options().plugins()->save_archive(this->archive_);
1095         }
1096
1097       this->archive_ = NULL;
1098     }
1099 }
1100
1101 // Class Lib_group static variables.
1102 unsigned int Lib_group::total_lib_groups;
1103 unsigned int Lib_group::total_members;
1104 unsigned int Lib_group::total_members_loaded;
1105
1106 Lib_group::Lib_group(const Input_file_lib* lib, Task* task)
1107   : Library_base(task), lib_(lib), members_()
1108 {
1109   this->members_.resize(lib->size());
1110 }
1111
1112 const std::string&
1113 Lib_group::do_filename() const
1114 {
1115   std::string *filename = new std::string("/group/");
1116   return *filename;
1117 }
1118
1119 // Select members from the lib group and add them to the link.  We walk
1120 // through the members, and check if each one up should be included.
1121 // If the object says it should be included, we do so.  We have to do
1122 // this in a loop, since including one member may create new undefined
1123 // symbols which may be satisfied by other members.
1124
1125 void
1126 Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
1127                        Input_objects* input_objects)
1128 {
1129   ++Lib_group::total_lib_groups;
1130
1131   Lib_group::total_members += this->members_.size();
1132
1133   bool added_new_object;
1134   do
1135     {
1136       added_new_object = false;
1137       unsigned int i = 0;
1138       while (i < this->members_.size())
1139         {
1140           const Archive_member& member = this->members_[i];
1141           Object* obj = member.obj_;
1142           std::string why;
1143
1144           // Skip files with no symbols. Plugin objects have
1145           // member.sd_ == NULL.
1146           if (obj != NULL
1147               && (member.sd_ == NULL || member.sd_->symbol_names != NULL))
1148             {
1149               Archive::Should_include t = obj->should_include_member(symtab,
1150                                                                      layout,
1151                                                                      member.sd_,
1152                                                                      &why);
1153
1154               if (t != Archive::SHOULD_INCLUDE_YES)
1155                 {
1156                   ++i;
1157                   continue;
1158                 }
1159
1160               this->include_member(symtab, layout, input_objects, member);
1161
1162               added_new_object = true;
1163             }
1164           else
1165             {
1166               if (member.sd_ != NULL)
1167                 {
1168                   // The file must be locked in order to destroy the views
1169                   // associated with it.
1170                   gold_assert(obj != NULL);
1171                   obj->lock(this->task_);
1172                   delete member.sd_;
1173                   obj->unlock(this->task_);
1174                 }
1175             }
1176
1177           this->members_[i] = this->members_.back();
1178           this->members_.pop_back();
1179         }
1180     }
1181   while (added_new_object);
1182 }
1183
1184 // Include a lib group member in the link.
1185
1186 void
1187 Lib_group::include_member(Symbol_table* symtab, Layout* layout,
1188                           Input_objects* input_objects,
1189                           const Archive_member& member)
1190 {
1191   ++Lib_group::total_members_loaded;
1192
1193   Object* obj = member.obj_;
1194   gold_assert(obj != NULL);
1195
1196   Pluginobj* pluginobj = obj->pluginobj();
1197   if (pluginobj != NULL)
1198     {
1199       pluginobj->add_symbols(symtab, NULL, layout);
1200       return;
1201     }
1202
1203   Read_symbols_data* sd = member.sd_;
1204   gold_assert(sd != NULL);
1205   obj->lock(this->task_);
1206   if (input_objects->add_object(obj))
1207     {
1208       if (layout->incremental_inputs() != NULL)
1209         layout->incremental_inputs()->report_object(obj, member.arg_serial_,
1210                                                     this, NULL);
1211       obj->layout(symtab, layout, sd);
1212       obj->add_symbols(symtab, sd, layout);
1213     }
1214   delete sd;
1215   // Unlock the file for the next task.
1216   obj->unlock(this->task_);
1217 }
1218
1219 // Iterate over all unused symbols, and call the visitor class V for each.
1220
1221 void
1222 Lib_group::do_for_all_unused_symbols(Symbol_visitor_base* v) const
1223 {
1224   // Files are removed from the members list when used, so all the
1225   // files remaining on the list are unused.
1226   for (std::vector<Archive_member>::const_iterator p = this->members_.begin();
1227        p != this->members_.end();
1228        ++p)
1229     {
1230       Object* obj = p->obj_;
1231       obj->for_all_global_symbols(p->sd_, v);
1232     }
1233 }
1234
1235 // Print statistical information to stderr.  This is used for --stats.
1236
1237 void
1238 Lib_group::print_stats()
1239 {
1240   fprintf(stderr, _("%s: lib groups: %u\n"),
1241           program_name, Lib_group::total_lib_groups);
1242   fprintf(stderr, _("%s: total lib groups members: %u\n"),
1243           program_name, Lib_group::total_members);
1244   fprintf(stderr, _("%s: loaded lib groups members: %u\n"),
1245           program_name, Lib_group::total_members_loaded);
1246 }
1247
1248 Task_token*
1249 Add_lib_group_symbols::is_runnable()
1250 {
1251   if (this->readsyms_blocker_ != NULL && this->readsyms_blocker_->is_blocked())
1252     return this->readsyms_blocker_;
1253   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
1254     return this->this_blocker_;
1255   return NULL;
1256 }
1257
1258 void
1259 Add_lib_group_symbols::locks(Task_locker* tl)
1260 {
1261   tl->add(this, this->next_blocker_);
1262 }
1263
1264 void
1265 Add_lib_group_symbols::run(Workqueue*)
1266 {
1267   // For an incremental link, begin recording layout information.
1268   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
1269   if (incremental_inputs != NULL)
1270     incremental_inputs->report_archive_begin(this->lib_, 0, NULL);
1271
1272   this->lib_->add_symbols(this->symtab_, this->layout_, this->input_objects_);
1273
1274   if (incremental_inputs != NULL)
1275     incremental_inputs->report_archive_end(this->lib_);
1276 }
1277
1278 Add_lib_group_symbols::~Add_lib_group_symbols()
1279 {
1280   if (this->this_blocker_ != NULL)
1281     delete this->this_blocker_;
1282   // next_blocker_ is deleted by the task associated with the next
1283   // input file.
1284 }
1285
1286 } // End namespace gold.